Delete UrlValidityCheckerFactory and move singleton to InstantService

Classes with only static functions are not allowed as per the style
guide (https://google.github.io/styleguide/cppguide.html#Nonmember,_Static_Member,_and_Global_Functions).

Instead, InstantService will own the single UrlValidityChecker instance.

Bug: 874194
Change-Id: Ia4fa35abfdfde3e0d64b268c11c9b7a82fedc126
Reviewed-on: https://chromium-review.googlesource.com/c/1283947
Commit-Queue: Kristi Park <kristipark@chromium.org>
Reviewed-by: Mathieu Perreault <mathp@chromium.org>
Reviewed-by: Greg Thompson <grt@chromium.org>
Cr-Commit-Position: refs/heads/master@{#600508}

chrome/browser/BUILD.gn

@@ -2940,8 +2940,6 @@ jumbo_split_static_library("browser") {
       "search/one_google_bar/one_google_bar_service_observer.h",
       "search/search_engine_base_url_tracker.cc",
       "search/search_engine_base_url_tracker.h",
-      "search/url_validity_checker_factory.cc",
-      "search/url_validity_checker_factory.h",
       "signin/mutable_profile_oauth2_token_service_delegate.cc",
       "signin/mutable_profile_oauth2_token_service_delegate.h",
       "signin/signin_promo.cc",

chrome/browser/search/instant_service.cc

@@ -8,13 +8,17 @@
 
 #include "base/bind.h"
 #include "base/files/file_util.h"
+#include "base/no_destructor.h"
 #include "base/path_service.h"
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/task/post_task.h"
+#include "base/time/default_tick_clock.h"
 #include "base/time/time.h"
 #include "build/build_config.h"
+#include "chrome/browser/browser_process.h"
 #include "chrome/browser/chrome_notification_types.h"
+#include "chrome/browser/net/system_network_context_manager.h"
 #include "chrome/browser/ntp_tiles/chrome_most_visited_sites_factory.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/search/instant_io_context.h"
@@ -25,7 +29,6 @@
 #include "chrome/browser/search/ntp_icon_source.h"
 #include "chrome/browser/search/search.h"
 #include "chrome/browser/search/thumbnail_source.h"
-#include "chrome/browser/search/url_validity_checker_factory.h"
 #include "chrome/browser/search_engines/template_url_service_factory.h"
 #include "chrome/browser/themes/theme_properties.h"
 #include "chrome/browser/themes/theme_service.h"
@@ -41,6 +44,7 @@
 #include "components/prefs/pref_registry_simple.h"
 #include "components/prefs/pref_service.h"
 #include "components/search/search.h"
+#include "components/search/url_validity_checker_impl.h"
 #include "components/search_engines/template_url_service.h"
 #include "components/search_engines/template_url_service_observer.h"
 #include "components/sync_preferences/pref_service_syncable.h"
@@ -50,6 +54,7 @@
 #include "content/public/browser/notification_types.h"
 #include "content/public/browser/render_process_host.h"
 #include "content/public/browser/url_data_source.h"
+#include "services/network/public/cpp/shared_url_loader_factory.h"
 #include "ui/gfx/color_utils.h"
 
 namespace {
@@ -809,9 +814,14 @@ void InstantService::FallbackToDefaultThemeInfo() {
 }
 
 UrlValidityChecker* InstantService::GetUrlValidityChecker() {
+  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
   if (url_checker_for_testing_ != nullptr)
     return url_checker_for_testing_;
-  return UrlValidityCheckerFactory::GetUrlValidityChecker();
+  static base::NoDestructor<UrlValidityCheckerImpl> checker(
+      g_browser_process->system_network_context_manager()
+          ->GetSharedURLLoaderFactory(),
+      base::DefaultTickClock::GetInstance());
+  return checker.get();
 }
 
 // static

chrome/browser/search/instant_service.h

@@ -203,8 +203,9 @@ class InstantService : public KeyedService,
   // chrome-search://local-ntp/background.jpg
   void SetBackgroundToLocalResource();
 
-  // Returns UrlValidityCheckerFactory::GetInstance() or
-  // |url_checker_for_testing_| if not null.
+  // Returns the owned instance of UrlValidityChecker or
+  // |url_checker_for_testing_| if not null. Should only be called from the UI
+  // thread.
   UrlValidityChecker* GetUrlValidityChecker();
 
   Profile* const profile_;

chrome/browser/search/url_validity_checker_factory.cc

-// Copyright 2018 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "chrome/browser/search/url_validity_checker_factory.h"
-
-#include <memory>
-
-#include "base/time/default_tick_clock.h"
-#include "chrome/browser/browser_process.h"
-#include "chrome/browser/net/system_network_context_manager.h"
-#include "content/public/browser/browser_thread.h"
-#include "services/network/public/cpp/shared_url_loader_factory.h"
-
-// static
-UrlValidityChecker* UrlValidityCheckerFactory::GetUrlValidityChecker() {
-  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
-  static base::NoDestructor<UrlValidityCheckerImpl> checker(
-      g_browser_process->system_network_context_manager()
-          ->GetSharedURLLoaderFactory(),
-      base::DefaultTickClock::GetInstance());
-  return checker.get();
-}
-
-UrlValidityCheckerFactory::UrlValidityCheckerFactory() = default;
-
-UrlValidityCheckerFactory::~UrlValidityCheckerFactory() = default;

chrome/browser/search/url_validity_checker_factory.h

-// Copyright 2018 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef CHROME_BROWSER_SEARCH_URL_VALIDITY_CHECKER_FACTORY_H_
-#define CHROME_BROWSER_SEARCH_URL_VALIDITY_CHECKER_FACTORY_H_
-
-#include "base/macros.h"
-#include "base/no_destructor.h"
-#include "components/search/url_validity_checker_impl.h"
-
-// Singleton that owns a single UrlValidityCheckerImpl instance. Should only be
-// called from the UI thread.
-class UrlValidityCheckerFactory {
- public:
-  static UrlValidityChecker* GetUrlValidityChecker();
-
- private:
-  friend class base::NoDestructor<UrlValidityCheckerFactory>;
-
-  UrlValidityCheckerFactory();
-  ~UrlValidityCheckerFactory();
-
-  DISALLOW_COPY_AND_ASSIGN(UrlValidityCheckerFactory);
-};
-
-#endif  // CHROME_BROWSER_SEARCH_URL_VALIDITY_CHECKER_FACTORY_H_